Schorlomite Garnet: Gemstone Information
Schorlomite Garnet Occurs principally in alkaline igneous rocks such as nepheline-syenite and related types; also in skarns. Originally found in carbonatite at Magnet Cove, Arkansas, USA; also in the USA in the mafic alkaline complex at Rainy Creek, Montana. Crystals more than 8 cm diameter from the Ice River alkaline complex, BC, Canada. It also occurs at: Iivaara (Ijola), Lääni, Finland, in an alkaline complex; in a spurrite skarn at Fuka, Japan. Complexly zoned Ti-rich melanite-shorlomite garnets are obtained from Ambadungar carbonatite-alkali complex, Deccan Igneous Province, Gujarat State, India.
Forms a series with andradite:
Ca3Ti2 4+ (Fe23+Si)O12–Ca3Fe2 3+(SiO4)3 and is closely related to melanite (titanian andradite).
Refractive Index: 1.94–1.98
Specific Gravity: 3.77–3.93
Conchoidal – Fractures developed in brittle materials characterized by smoothly curving surfaces.
Colour – Dark brown, reddish brown to black.
Lustre – Vitreous to metallic
Rarely utilized as a gemstone although it has been used as black cabochon material.